diff --git a/2024/21/main-1.cpp b/2024/21/main-1.cpp
new file mode 100644
index 0000000..5202763
--- /dev/null
+++ b/2024/21/main-1.cpp
@@ -0,0 +1,108 @@
+#include "../../include/aoc.hpp"
+#include <bits/stdc++.h>
+using namespace std;
+
+const int ml = 2;
+
+unordered_map<char, icoord> npad = {
+	{'7', {0, 0}}, {'8', {0, 1}}, {'9', {0, 2}}, {'4', {1, 0}},
+	{'5', {1, 1}}, {'6', {1, 2}}, {'1', {2, 0}}, {'2', {2, 1}},
+	{'3', {2, 2}}, {'0', {3, 1}}, {'A', {3, 2}},
+};
+
+unordered_map<char, icoord> dpad = {
+	{'^', {0, 1}}, {'A', {0, 2}}, {'<', {1, 0}}, {'v', {1, 1}}, {'>', {1, 2}},
+};
+
+unordered_map<icoord, char> dirs = {
+	{{-1, 0}, '^'},
+	{{0, 1}, '>'},
+	{{1, 0}, 'v'},
+	{{0, -1}, '<'},
+};
+
+inline size_t hc(icoord a, icoord b, int level) {
+	return (a.x) | (a.y << 4) | (b.x << 8) | (b.y << 12) | (level << 16);
+}
+
+int main() {
+	ios::sync_with_stdio(0);
+	cin.tie(0);
+
+	unordered_set<icoord> npads, dpads;
+	for (auto &p : npad) {
+		npads.insert(p.second);
+	}
+	for (auto &p : dpad) {
+		dpads.insert(p.second);
+	}
+
+	unordered_map<size_t, int> mm;
+	for (icoord start : dpads) {
+		for (icoord end : dpads) {
+			auto d = start - end;
+			mm[hc(start, end, 0)] = abs(d.x) + abs(d.y);
+		}
+	}
+
+	for (int level = 1; level <= ml; level++) {
+		auto &pads = (level == ml) ? npads : dpads;
+		for (auto start : pads) {
+			mm[hc(start, start, level)] = 0;
+			for (auto end : pads) {
+				if (end == start) {
+					continue;
+				}
+				int best = -1;
+				icoord d = end - start;
+				auto xc = dpad[(d.x > 0) ? 'v' : '^'];
+				auto yc = dpad[(d.y > 0) ? '>' : '<'];
+				if (d.x == 0) {
+					best = abs(d.y);
+					best += mm[hc(dpad['A'], yc, level - 1)];
+					best += mm[hc(yc, dpad['A'], level - 1)];
+				} else if (d.y == 0) {
+					best = abs(d.x);
+					best += mm[hc(dpad['A'], xc, level - 1)];
+					best += mm[hc(xc, dpad['A'], level - 1)];
+				} else {
+					for (int i = 0; i < 2; i++) {
+						icoord mid;
+						ll score = abs(d.x) + abs(d.y);
+						if (i == 0) {
+							mid = icoord(start.x, end.y);
+							score += mm[hc(dpad['A'], yc, level - 1)];
+							score += mm[hc(yc, xc, level - 1)];
+							score += mm[hc(xc, dpad['A'], level - 1)];
+						} else {
+							mid = icoord(end.x, start.y);
+							score += mm[hc(dpad['A'], xc, level - 1)];
+							score += mm[hc(xc, yc, level - 1)];
+							score += mm[hc(yc, dpad['A'], level - 1)];
+						}
+						if (pads.contains(mid) &&
+							(best == -1 || score < best)) {
+							best = score;
+						}
+					}
+				}
+				mm[hc(start, end, level)] = best;
+			}
+		}
+	}
+
+	int tcount = 0;
+	string line;
+	while (getline(cin, line)) {
+		int count = 0;
+		auto pos = npad['A'];
+		for (char c : line) {
+			auto newpos = npad[c];
+			count += mm[hc(pos, newpos, ml)] + 1;
+			pos = newpos;
+		}
+		tcount += count * stoi(line.substr(0, 3));
+	}
+
+	cout << tcount << '\n';
+}
diff --git a/2024/21/main-2.cpp b/2024/21/main-2.cpp
new file mode 100644
index 0000000..0f83024
--- /dev/null
+++ b/2024/21/main-2.cpp
@@ -0,0 +1,108 @@
+#include "../../include/aoc.hpp"
+#include <bits/stdc++.h>
+using namespace std;
+
+const int ml = 25;
+
+unordered_map<char, icoord> npad = {
+	{'7', {0, 0}}, {'8', {0, 1}}, {'9', {0, 2}}, {'4', {1, 0}},
+	{'5', {1, 1}}, {'6', {1, 2}}, {'1', {2, 0}}, {'2', {2, 1}},
+	{'3', {2, 2}}, {'0', {3, 1}}, {'A', {3, 2}},
+};
+
+unordered_map<char, icoord> dpad = {
+	{'^', {0, 1}}, {'A', {0, 2}}, {'<', {1, 0}}, {'v', {1, 1}}, {'>', {1, 2}},
+};
+
+unordered_map<icoord, char> dirs = {
+	{{-1, 0}, '^'},
+	{{0, 1}, '>'},
+	{{1, 0}, 'v'},
+	{{0, -1}, '<'},
+};
+
+inline size_t hc(icoord a, icoord b, int level) {
+	return (a.x) | (a.y << 4) | (b.x << 8) | (b.y << 12) | (level << 16);
+}
+
+int main() {
+	ios::sync_with_stdio(0);
+	cin.tie(0);
+
+	unordered_set<icoord> npads, dpads;
+	for (auto &p : npad) {
+		npads.insert(p.second);
+	}
+	for (auto &p : dpad) {
+		dpads.insert(p.second);
+	}
+
+	unordered_map<size_t, ll> mm;
+	for (icoord start : dpads) {
+		for (icoord end : dpads) {
+			auto d = start - end;
+			mm[hc(start, end, 0)] = abs(d.x) + abs(d.y);
+		}
+	}
+
+	for (int level = 1; level <= ml; level++) {
+		auto &pads = (level == ml) ? npads : dpads;
+		for (auto start : pads) {
+			mm[hc(start, start, level)] = 0;
+			for (auto end : pads) {
+				if (end == start) {
+					continue;
+				}
+				ll best = -1;
+				icoord d = end - start;
+				auto xc = dpad[(d.x > 0) ? 'v' : '^'];
+				auto yc = dpad[(d.y > 0) ? '>' : '<'];
+				if (d.x == 0) {
+					best = abs(d.y);
+					best += mm[hc(dpad['A'], yc, level - 1)];
+					best += mm[hc(yc, dpad['A'], level - 1)];
+				} else if (d.y == 0) {
+					best = abs(d.x);
+					best += mm[hc(dpad['A'], xc, level - 1)];
+					best += mm[hc(xc, dpad['A'], level - 1)];
+				} else {
+					for (int i = 0; i < 2; i++) {
+						icoord mid;
+						ll score = abs(d.x) + abs(d.y);
+						if (i == 0) {
+							mid = icoord(start.x, end.y);
+							score += mm[hc(dpad['A'], yc, level - 1)];
+							score += mm[hc(yc, xc, level - 1)];
+							score += mm[hc(xc, dpad['A'], level - 1)];
+						} else {
+							mid = icoord(end.x, start.y);
+							score += mm[hc(dpad['A'], xc, level - 1)];
+							score += mm[hc(xc, yc, level - 1)];
+							score += mm[hc(yc, dpad['A'], level - 1)];
+						}
+						if (pads.contains(mid) &&
+							(best == -1 || score < best)) {
+							best = score;
+						}
+					}
+				}
+				mm[hc(start, end, level)] = best;
+			}
+		}
+	}
+
+	ll tcount = 0;
+	string line;
+	while (getline(cin, line)) {
+		ll count = 0;
+		auto pos = npad['A'];
+		for (char c : line) {
+			auto newpos = npad[c];
+			count += mm[hc(pos, newpos, ml)] + 1;
+			pos = newpos;
+		}
+		tcount += count * stoi(line.substr(0, 3));
+	}
+
+	cout << tcount << '\n';
+}